1. Field of The Invention
The present invention relates to novel adducts of menadione with a derivative of pyridine such as pyridoxine, pyridoxal or pyridoxamine, which adduct has vitamin B.sub.6 activity and vitamin K activity, and is useful in animal feed premix and compositions.
2. Description of The Prior Art
It has long been known that among the vitamin K active substances (VKAS) menadione sodium bisulfite (MSB), the adduct of of sodium bisulfite and menadione (2-methyl-1,4-naphthoquinone) provides better vitamin K (antihemorrhagic) activity on an equal weight basis than menadione itself. Menadione is one of the first synthetic analogues of the natural vitamin K's of vegetable or animal origin.
This quality has been partially explained on the basis of the high water solubility of the adduct (menadione is oil soluble) and the consequently easier and more effective absorption into the organism receiving this form of VKAS.
A further improvement was the discovery of the compound menadione dimethylpyrimidinol bisulfite (MPB) which is disclosed and described in U.S. Pat. No. 3,328,169 issued to Heterochemical Corporation, Valley Stream, N.Y. MPB is a compound in which the sodium atom of MSB was substituted by a weak organic base, more precisely a particular pyrimidine base. This resulting compound possessed a remarkably high vitamin K activity (P. Griminger, Poultry Science 44,210 (1965); Dua, Day ibid 45,94 (1966)) and a better stability than MSB when mixed with other vitamins, minerals, etc. in animal feed supplement.